Pull out your knitting needles: Grandma was on to something with that ever-lengthening scarf tucked in her handbag. Whether you're into gardening, fixing up vintage cars, or even cross-stitching Drake lyrics like Taylor Swift, new research has found that hobbies are just as important to good health as exercise is, thanks to their ability to relieve stress. That's right, your love of running model trains is just as good for you as your love of running.

The study, published in the Annals of Behavioral Medicine, followed over 100 adults as they went about their daily activities. Participants wore heart monitors and also completed surveys periodically to report their activities and how they were feeling. After three days, the researchers found that people who engaged in leisure activities were 34 percent less stressed and 18 percent less sad during the activities. Not only did they report feeling happier, but their heart rates were lower—and the calming effect lasted for hours.

Surprisingly, the scientists say that it didn't seem to matter much what the participants did just so long as it was something they deeply enjoyed. No matter the passion, people showed the same huge decrease in stress. (Add that tip to our 5 Easy Ways to Start Your Day Stress-Free.)

"If we start thinking about that beneficial carryover effect day after day, year after year, it starts to make sense how leisure can help improve health in the long term," Matthew Zawadzki, Ph.D., assistant professor of psychology at the University of California, Merced, and lead author of the paper, told NPR. "Stress causes a build-up of higher heart rate, blood pressure, and hormone levels, so the more we can prevent this overworked state, the less of a load it builds up."